LOL. Yes, that is pretty much what it means.
After WW2, the US really had very little damage. And the rest of the world had taken a very serious beating, requiring a generation to repair. We were the big dog, had the highest standard of living, and no competition at all as the place where the living was best.
However, that was yesterday. Europe recovered, evolved politically, and today many places boast a living standard that exceeds that in the US. But all too many of our 'Conservatives' are still mentally in the '50's, and cannot admit that other peoples have exceeded us in many ways. Nor can they admit that we should be learning from what they are doing better than we are. So they mouth nonsense like 'Making America Great Again'. Well, we never ceased being great. It is simply that much of the rest of the world is also a great place to be now. And they simply cannot accept that.
For the rest of us, that is a good thing. And after I retire, I intend to see much of the rest of the world, especially Great Britain, where most my roots are.